A box is to be made where the material for the sides and the lid cost $0.20 per square foot and the cost for the bottom is $0.650.65 per square foot. Find the dimensions of a box with volume 1010 cubic feet that has minimum cost.

The perimeter of ? cde is 55 cm. a rhombus dmfn is inscribed in this triangle so that vertices m, f, and n lie on the sides cd , ce , and de respectively. find cd and de if cf=8 cm and ef=12 cm. the answer is not cd=20 and de=15. i have tried that one, it does not work.